Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. It only takes a minute to sign up.
Sign up to join this community
Suppose a process, among other things, is posting https requests, for example with curl.
Assuming I have root privileges, is there a way to intercept such requests and respond with an http error or, even better with acknowledgment?
I am using an embedded device, so I have limited access to software libraries.
What you are asking for is called a proxy http server.
The software receives http requests and passes them on or rejects them (logging too) It needn't sit on your embeded device, however your device would need to be configured to access the proxy instead of going directly to the internet.
apache nginx are two examples of web servers that can act as proxy servers. squid is a sophisticated proxy server which can handle many protocols. charles is another, but paid for program (although there is a free trial period).
If you need to ensure that all requests are via the proxy then you would also want to set up your network to prevent direct requests from the device going directly to the internet. (you can't do that if your device hosts the proxy).
